Eissa El-Sayed Hemdan, Hendam Basma M, Dighiesh Hagar Sedeek, Abd Elnabi Heba E, Sakr Salah El-Sayed, Kabary Hoda, Abdel Rahman Afaf N, Eissa Moaheda E H, Ahmed Norhan H
Fish Research Centre, Faculty of Agricultural Environmental Sciences, Arish University, El-Arish, Egypt.
Department of Animal Wealth Development, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt.
Fish Shellfish Immunol. 2025 Jan;156:110059. doi: 10.1016/j.fsi.2024.110059. Epub 2024 Nov 28.
In shrimp aquaculture, enhancing health and disease resistance is crucial for sustainable production. This study investigates the pioneering effects of astaxanthin-enriched microalgal powder from Haematococcus pluvialis (HP) on Pacific white shrimp (Litopenaeus vannamei), focusing on growth efficiency, body composition, immune and antioxidant responses, intestinal health, histopathology, gene expression, and resistance against Fusarium solani. Shrimp (initial weight 5.27 ± 0.12 g) were separated into four groups and fed diets supplemented with HP at concentrations of 0, 0.5, 1, and 1.5 g/kg feed (control, HP , HP, and HP), respectively, for 8 weeks. The outcomes revealed marked improvements in growth, feed utilization, and survival rate of the HP-fed groups. The improvement was dose-dependent. The protein and ash content increased and the lipid decreased with HP supplementation. A dose-dependent augmented antioxidant-immune response was obvious in the HP-fed groups. This is proven by the high level of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase, total hemocyte count, respiratory burst, lysozyme (LYZ), phenoloxidase (PO), and phagocytic activity with up-regulation of proPO, LYZ, SOD, and CAT genes. Dietary HP influenced the intestinal bacterial community, where it reduced total aerobic and fecal bacteria and rose total probiotic bacteria and Clostridium counts. Histological investigation showed increased secretory vesicles within B-cells in the hepato-pancreas and larger muscle fibers in the HP-fed groups. Additionally, dietary HP notably lowered mortality rates upon the F. solani challenge, with a reduction from 65.00 % in the control to 45.00 %, 35.00%, and 35.00 % in the HP , HP, and HP groups, respectively. Our study recommends adopting dietary HP at the optimal dose of 1.2 g/kg diet relying on the broken line regression model. This study provides valuable insights into the potential of HP as a dietary supplement to improve the health, growth, and disease resistance of L. vannamei, marking a significant advancement in shrimp aquaculture.
在对虾养殖中，增强健康和抗病能力对于可持续生产至关重要。本研究调查了雨生红球藻富含虾青素的微藻粉（HP）对凡纳滨对虾的开创性影响，重点关注生长效率、身体组成、免疫和抗氧化反应、肠道健康、组织病理学、基因表达以及对茄病镰刀菌的抗性。将对虾（初始体重5.27±0.12克）分为四组，分别投喂添加浓度为0、0.5、1和1.5克/千克饲料的HP饲料（对照组、HP、HP和HP），持续8周。结果显示，投喂HP饲料的组在生长、饲料利用率和存活率方面有显著改善。这种改善呈剂量依赖性。添加HP后，蛋白质和灰分含量增加，脂质含量降低。在投喂HP饲料的组中，抗氧化免疫反应呈剂量依赖性增强。这通过超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶、总血细胞计数、呼吸爆发、溶菌酶（LYZ）、酚氧化酶（PO）的高水平以及前酚氧化酶、LYZ、SOD和CAT基因的上调所证明。饲料中的HP影响肠道细菌群落，降低了总需氧菌和粪便细菌数量，增加了总益生菌和梭菌数量。组织学研究表明，投喂HP饲料的组肝胰腺中B细胞内的分泌小泡增加，肌肉纤维更大。此外，饲料中的HP显著降低了茄病镰刀菌攻毒后的死亡率，对照组从65.00%分别降至HP、HP和HP组的45.00%、35.00%和35.00%。我们的研究建议根据折线回归模型采用1.2克/千克饲料的最佳剂量投喂HP。本研究为HP作为饲料添加剂改善凡纳滨对虾的健康、生长和抗病能力的潜力提供了有价值的见解，标志着对虾养殖的重大进展。
